1. Field of the Invention
The present invention relates to inductor fabrication technology and more particularly, to a method for making a shielded inductor, which employs an injection-molding technique to make an inductor body for shielded inductor.
2. Description of the Related Art
In U.S. Pat. No. 6,204,744 and No. 6,460,244, a method for making a high current, low profile inductor is disclosed. This method of making a high current, low profile inductor includes a magnetic material completely surrounding a conductive coil to form an inductor body. As the inductor body is formed of a magnetic material, it provides a shielding effect, enhancing the effects of the inductor.
In the cited U.S. Pat. No. 6,204,744, the inductor body is free from ferrite materials, and made by uniformly mixing first and second powdered iron particles having electrical characteristics different from one another and then pressure-molding the uniform mixture around a wire coil and then sintering the molded mixture.
In the cited U.S. Pat. No. 6,460,244, powdered magnetic material free from voids is used, and pressure-molding is employed to mold powdered magnetic material into the desired external inductor body.
In the above two cited US Patents, pressure-molding is employed to make the inductor body. Employing the pressure-molding technique slows down the fabrication. During molding, the conductive coil must be put in the molding mold. Further, the mold design is complicated and not adjustable for molding an inductor body having a different configuration.